Method for producing a polyisocyanurate composite material

A process for producing a composite polyisocyanurate material, comprising the following steps:

• a) providing a polyisocyanate composition A) consisting of one or more oligomeric polyisocyanates and not more than 0.5% by weight of one or more unconverted monomeric diisocyanates, based on the weight of the polyisocyanate composition A), and
• b) catalytically trimerizing the polyisocyanate composition A) in the presence of at least one fibrous filler B) and of a trimerization catalyst C) to give the composite polyisocyanurate material,
• wherein the trimerization catalyst C) comprises at least one of a metal salt and a quaternary ammonium salt and an optional polyether;
• and the trimerization catalyst C) is provided in an amount of from 0.4% to 15.0% by weight based on the weight of the polyisocyanate composition A);
• wherein each of the one or more oligomeric polyisocyanates is prepared by:
• reacting an excess of monomeric diisocyanate, yielding the oligomeric polyisocyanate and the unconverted monomeric diisocyanate, and removing at least a portion of the unconverted monomeric diisocyanate;
• and
• wherein at least 70 wt % of the one or more oligomeric polyisocyanates are oligomeric aliphatic polyisocyanates and/or oligomeric alicyclic polyisocyanates.